Warning: Unusual traffic from your computer. Why is this happening? [duplicate]

This warning keeps showing up and I have no idea why. My OS is Ubuntu 14.04 LTS.

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About this page

Our systems have detected unusual traffic from your computer network. This page checks to see if it's really you sending the requests, and not a robot. Why did this happen? IP address: XXX.XXX.XXX.XXX Time: 2016-01-20T12:04:04Z URL:

Can someone help me out?

1 Answer

From Google's "Why did this happen":

This page appears when Google automatically detects requests coming from your computer network which appear to be in violation of the Terms of Service. The block will expire shortly after those requests stop.

This traffic may have been sent by malicious software, a browser plug-in, or a script that sends automated requests. If you share your network connection, ask your administrator for help — a different computer using the same IP address may be responsible. Learn more

Sometimes you may see this page if you are using advanced terms that robots are known to use, or sending requests very quickly.

So, apparently your are (most likely) searching items or in a way that Google interprets as a search a robot is likely to use. As noted, the flag should expire after your flagged activity stops (say, you quit using Google for a while).